Since @smartron abandoned SRT.phone and it's users from Android update, developers are making sure that users do get taste of Android sweets.
Here is a pie Custom ROM to try.
1. Pixel experience ROM: Released and unofficial. Stable with some know bugs.
2. Arrow OS: Not released yet but almost stable if you don't care hotspot works or not.
Keep visiting this place for video review of Arrow OS.
Video Coming Soon